diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5f3a4532..9bb7485c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 Full release notes with details on each version: [GitHub Releases](https://github.com/safishamsi/graphify/releases)
 
+## 0.4.5 (2026-04-12)
+
+- Fix: MCP server no longer crashes with `ValidationError` on blank lines sent between JSON messages by some clients (#201)
+
 ## 0.4.4 (2026-04-12)
 
 - Fix: `watch` now preserves INFERRED/AMBIGUOUS edges (code↔doc rationale links) across rebuilds — previously all cross-type edges were dropped (#261)
diff --git a/graphify/serve.py b/graphify/serve.py
index 279b5d31..a0778343 100644
--- a/graphify/serve.py
+++ b/graphify/serve.py
@@ -108,6 +108,36 @@ def _find_node(G: nx.Graph, label: str) -> list[str]:
             if term in d.get("label", "").lower() or term == nid.lower()]
 
 
+def _filter_blank_stdin() -> None:
+    """Filter blank lines from stdin before MCP reads it.
+
+    Some MCP clients (Claude Desktop, etc.) send blank lines between JSON
+    messages. The MCP stdio transport tries to parse every line as a
+    JSONRPCMessage, so a bare newline triggers a Pydantic ValidationError.
+    This installs an OS-level pipe that relays stdin while dropping blanks.
+    """
+    import os
+    import threading
+
+    r_fd, w_fd = os.pipe()
+    saved_fd = os.dup(sys.stdin.fileno())
+
+    def _relay() -> None:
+        try:
+            with open(saved_fd, "rb") as src, open(w_fd, "wb") as dst:
+                for line in src:
+                    if line.strip():
+                        dst.write(line)
+                        dst.flush()
+        except Exception:
+            pass
+
+    threading.Thread(target=_relay, daemon=True).start()
+    os.dup2(r_fd, sys.stdin.fileno())
+    os.close(r_fd)
+    sys.stdin = open(0, "r", closefd=False)
+
+
 def serve(graph_path: str = "graphify-out/graph.json") -> None:
     """Start the MCP server. Requires pip install mcp."""
     try:
@@ -325,6 +355,7 @@ def serve(graph_path: str = "graphify-out/graph.json") -> None:
         async with stdio_server() as streams:
             await server.run(streams[0], streams[1], server.create_initialization_options())
 
+    _filter_blank_stdin()
     asyncio.run(main())
 
 
diff --git a/pyproject.toml b/pyproject.toml
index 3c9f34f9..baae916c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "graphifyy"
-version = "0.4.4"
+version = "0.4.5"
 description = "AI coding assistant skill (Claude Code, Codex, OpenCode, Cursor, OpenClaw, Factory Droid, Trae) - turn any folder of code, docs, papers, images, or videos into a queryable knowledge graph"
 readme = "README.md"
 license = { file = "LICENSE" }